• Journal of Astronomy and Space Sciences
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• v.33 no.3
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• pp.185-196
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• 2016

New multiband BVRI light curves of NSVS 1461538 were obtained as a byproduct during the photometric observations of our program star PV Cas for three years from 2011 to 2013. The light curves indicate characteristics of a typical W-subtype W UMa eclipsing system, displaying a flat bottom at primary eclipse and the O'Connell effect, rather than those of an Algol/b Lyrae eclipsing variable classified by the northern sky variability survey (NSVS). A total of 35 times of minimum lights were determined from our observations (20 timings) and the SuperWASP measurements (15 ones). A period study with all the timings shows that the orbital period may vary in a sinusoidal manner with a period of about 5.6 yr and a small semi-amplitude of about 0.008 day. The cyclical period variation can be interpreted as a light-time effect due to a tertiary body with a minimum mass of 0.71 M_⊙. Simultaneous analysis of the multiband light curves using the 2003 version of the Wilson-Devinney binary model shows that NSVS 1461538 is a genuine W-subtype W UMa contact binary with the hotter primary component being less massive and the system shows a low mass ratio of q(m_c/m_h)=3.51, a high orbital inclination of 88.7°, a moderate fill-out factor of 30 %, and a temperature difference of ΔT=412 K. The O'Connell effect can be similarly explained by cool spots on either the hotter primary star or the cool secondary star. A small third-light corresponding to about 5 % and 2 % of the total systemic light in the B and V bandpasses, respectively, supports the third-body hypothesis proposed by the period study. Preliminary absolute dimensions of the system were derived and used to look into its evolutionary status with other W UMa binaries in the mass-radius and mass-luminosity diagrams. A possible evolution scenario of the system was also discussed in the context of the mass vs mass ratio diagram.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.8
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• pp.1073-1077
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• 2001

Forty three 7-month old, Barbados Black $Belly{\times}Malin$ crossbred sheep were used for the trial. They were allotted into three treatment groups fed varying levels of oil palm (Elaeis guineensis) frond pellets and commercial sheep pellets. Treatment diets were 80% commercial pellet+20 % (% w/w) oil palm frond pellet (CON group, n=15), 50% commercial pellet+50% oil palm frond pellet (% w/w) (HAF group, n=14) and 80% oil palm frond pellet+20% (% w/w) commercial pellet (OPF group, n=14). The plasma fatty acid profiles from these animals were compared before and after 14 weeks of feeding. Results showed that total unsaturated fatty acid content in the CON group had increased by 10% (p<0.01) from the pre-treatment values. All three treatment groups had significantly different plasma n-6 and n-3 polyunsaturated fatty acid contents at the end of the trial. In fact, the CON group had significantly (p<0.01) more n-6 polyunsaturated fatty acid content compared to its own initial values, and also the values from the HAF and OPF groups. However there was a significant (p<0.01) decline in plasma n-3 polyunsaturated fatty acids in all groups. The final total unsaturated to saturated fatty acid content ratio was significantly (p<0.01) highest in the CON group, demonstrating the high plasma unsaturated fatty acid content in these animals. This study shows the plasma unsaturated fatty acids in sheep can be increased by dietary manipulation.

• Applied Biological Chemistry
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• v.30 no.3
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• pp.234-241
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• 1987

Conditions necessary for optimal plastein productivity from sardine protein hydrolysate using papain and pepsin were established. Sardine protein concentrate was hydrolyzed with pepsin yielding an approximate degree of hydrolysis of 77.2%. Enzyme induced plastein was optimized at: pH 6 for papain and pH 4 for pepsin; substrate concentrate, 50%(w/v) for papain and 40%(w/v) for pepsin; time of incubation, 24hr; enzyme/substrate ratio, 1 : 100(w/w). Plastein yields of 49.5% and 45.3% were found for papain and pepsin, respectively, when 10% trichloroacetic acid (TCA) was used as the precipitating agent. However, when plastein was precipitated by 50% ethanol, the yield was found to be 43.6% and 41.0% for papain and pepsin, respectively. Ethanol-precipitated plastein did not contain lipid and contained approximately 1.3% ash and 91.0% protein. In comparison, the TCA-precipitated plastein contained 74.2% protein, 0.5% lipid and 15.3% ash.

• Journal of Advanced Marine Engineering and Technology
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• v.7 no.2
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• pp.15-21
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• 1983

Preparing for treatment and management of the emulsified fuel oil which will be generalized henceforth, this paper is an attempt to examine the viscosity-temperature characteristics of emulsified heavy fuel oil which is mixed with water and emulsifier in various mixture ratio by mechanical mixer. The experimental results are summarized as follows: 1. The viscosity-temperature characteristics of the emulsified C & B grade heavy fuel oil mixed with water of same or less weight, is changed according to log.log(v+0.6)=b-3.8log T. 2. The emulsifier has to be added to the emulsified A grade heavy fuel oil mixed with water of same or less weight, because it is instable. Especially if the emulsifier is sodium stearate, it is added more than 0.3% of the weight of oil and water. 3. In the emulsified A grade heavy fuel oil mixed with water and emulsifier, the higher the ratio of water addition becomes, the higher the viscosity is and the more the viscosity-temperature slope decreases. But the higher the ratio of emulsifier addition is, the more the viscosity-temperature slope increases. In this case, the linearity of viscosity-temperature characteristic curve is poorer than that of B and C grade heavy fuel oil. 4. In the emulsified A grade heavy fuel oil mixed with emulsifier of 0.3% or less, the emulsion type is O/W type when water addition ratio is 40%, but it is W/O type when it is 10%, 20%, 30% and 50%.

• Korean Journal of Ecology and Environment
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• v.53 no.3
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• pp.304-310
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• 2020

Smart farm is a high-tech type of plant factory that artificially makes environmental conditions suitable for the growth of plants and manages them to automatically produce the desired plants regardless of seasons or space. This study was conducted by identifying the effects of Hertz and Duty ratio on the photosynthetic rate of ginseng, a medicinal crop, to find the optimal conditions for photosynthetic responses in smart farms. The light sources consisted of a total of 10 chambers using LED system, with 4 R+B(red+blue) mixed lights and 6 R+B+W (red+blue+white) mixed lights. In addition, the Hertz of the R+B mixed light was treated at 20, 60, 180, 540, 1620 and 4860 hz respectively. The R+B+W mixed light was treated with 60, 180, 540, and 1620 hz. Afterwards, experiments were conducted with the duty ratio of 30, 50, and 70%. As a result, the photosynthetic rate of ginseng according to duty ratio and Hertz was the highest at 60 hz when duty ratio was set to 50%. On the other hand, that was the lowest when the duty ratio was 30% at the same 60 hz. In addition, the photosynthetic rates were highest in the R+B mixed light and R+B+W mixed light at 60 hz. Therefore, the condition with the highest photosynthetic rate of ginseng in smart farms is 60 hz when the duty ratio in R+B mixed light is 50%.

• Fire Science and Engineering
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• v.26 no.1
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• pp.89-95
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• 2012

In this study, we were manufactured wood flour-HDPE composites by modular co-rotating twin screw extruder with L/D ratio of 42. We was measured cone calorimeter test and thermogravimetric analysis (TGA) to find the combustion characteristics and thermal properties for wood flour-HDPE composites. We then evaluated the effect of three additive-type flame retardants on fire resistance performance. The cone calorimeter test showed that the heat release rate (HRR) of untreated composites was the highest Peak HRR ($446.6kW/m^2$) as well as Mean HRR ($185.5kW/m^2$). From the TGA, it was shown that composites added flame retardants began early thermal decomposition and improved thermal stability.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.116-116
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• 2011

오늘날 표시장치는 경량, 고밀도, 고해상도 대면적화의 요구에 의해 TFT-LCD의 발전이 이루어졌다. TFT에는 반도체 재료로서, Poly-Si을 사용하는 Poly-Si TFT와 a-Si:H를 이용하는 a-Si;H TFT가 있는데 a-Si는 $350^{\circ}C$ 이하의 저온으로 제작이 가능하여 많이 사용되고 있다. 이러한 방향에 맞추어 bottom gate 구조의 a-Si TFT 실험을 진행하였다. P-type silicon substrate ($0.01{\sim}0.02{\Omega}-cm$)에 gate insulator 층인 SiNx (SiH4 : NH3 = 6:60)를 200nm 증착하였다. 그리고 그 위에 active layer 층인 a-Si (SiH4 : H2 : He =2.6 : 10 : 100)을 다른 RF power를 적용하여 100 nm 증착하였다. 그 위에 Source와 Drain 층은 Al 120 nm를 evaporator로 증착하였다. active layer, gate insulator 층은 ICP-CVD 장비를 이용하여 증착하였으며, 공정온도는 $300^{\circ}C$ 로 고정하였다. active layer층 증착시 RF power는 100W, 300W, 500W, 600W로 가변하였고, width/length는 100 um/8um로 고정하였다. 증착한 a-Si layer층을 Raman spectroscope, SEM 측정 하였으며, TFT 제작 후, VG-ID, VD-ID 측정을 통해 전기적 특성인 Threshold voltage, Subthreshold swing, Field effect mobility, ON/OFF current ratio를 비교해 보았다.

• Journal of the Korean Society of Propulsion Engineers
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• v.4 no.4
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• pp.50-58
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• 2000

Burning rate of the matrix propellant($r_{sb}$) and burning rate along the metal wire($r_w$) were measured and analyzed for the HTPB/AP/Al propellant embedded with Ag wire($\phi$0.15mm) according to weight % of RDX(0~20%). Variation of burning rate increment ratio($r_w$/$r_{sb}$) and pressure exponent(n) was studied for the nitramine propellant having 10% RDX embedded with three kinds of metal(Ag, Cu, and Ni-Cr) of which diameter range is between 0.1~0.6mm. Maximum burning rate increment ratio of the nitramine propellant embedded with Ag wire($\phi$0.1mm) was 5.94 at $20^{\cire}C$, 1000 psia, 16.4% faster than that of HTPB/AP propellant, it is because that autoignition temperature of the nitramine propellant was higher than that of HTPB/AP propellant. Standard deviation of absolute ($r_{wc}$/$r_{we}$)/$r_{we}$ calculated by using new empiracal equation composed of four dimensionless groups, is 6.11% less than that calculated by using original empirical equation composed of three dimensionless group. The new empiracal equation is derived from Buckingham pi theorem using the parameters such as thermal diffusivity, melting temperature. wire diameter, propellant sample diameter, frame temperature, autoignition temperature and matrix burning rate which influence on $r_w$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.5
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• pp.439-446
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• 1985

This study was designed to compare the lipid components among wild and cultured eel, Anguilla japonica, and conger eel, Astroconger myriaster. The lipid components of cultured eel were analyzed and compared with those of wild and conger eel. In the content of total lipid, the lipid content in cultured eel was slightly higher than that in wild one, but 2 times higher than that in conger eel. The lipid contents in edible portion of wild and cultured eel were 5 times higher than those in viscera, but the lipid content in edible portion of conger eel showed a similar trend to that in viscera. In the fatty acid composition of neutral lipid in edible portion, percentages of $C_{14:0},\;C_{16:0}\;and\;C_{18:1}$ in cultured eel were higher than those in wild one, while percentages of $C_{16:1},\;C_{18:2},\;C_{18:3},\;C_{20:4},\;C_{20:5},\;C_{22:5}\;and\;C_{22:6}$ lower, and percentages of $C_{18:0},\;C_{20:4}\;and\;C_{22:6}$ in conger eel were noticeably higher than those in wild and cultured eels. In the case of phospholipid in edible portion, percentages of $C_{18:0}\;and\;C_{18:2}$ in cultured eel were higher than those in wild one, while percentages of $C_{16:0},\;C_{16:1},\;C_{18:1},\;C_{18:3},\;C_{20:4},\;C_{20:5},\;C_{22:5}\;and\;C_{22:6}$ lower. The unsaturation (TUFA/TSFA) of neutral lipid was no significant difference among wild and cultured eel, and conger eel, but that of phospholipid in wild eel was higher than that in cultured eel and conger eel. The essential fatty acid content(TEFA) of neutral lipid in edible portion of wild eel was 3 times higher than that of cultured one. but the TEFA of phospholipid in edible portion was no significant difference among wild and cultured eels, and conger eel. The w3 highly unsaturated fatty acid content (w3 HUFA) of neutral lipid in edible portion of wild eel was 2.0 to 2.5 times higher than that of cultured eel and conger eel, but the w3 HUFA of phospholipid in edible portion of wild eel was noticeably higher than that of cultured eel and conger eel. In the ratio (A/B) of fatty acid content (A) in cultured eel to that (B) in diet, the A/B ratios of $C_{18:2}\;w6,\;C_{18:3}\;w3,\;C_{20:5}\;w3\;and\;C_{22:6}\;w3$ were 0.23 to 0.48 much lower than the other fatty acid. Consequently, it is considered that the ratios of w3 HUFA is related to the biosynthesis of polyenoic acid and growth rate of cultured eel.

• The Journal of the Acoustical Society of Korea
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• v.6 no.4
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• pp.55-63
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• 1987

Modified $PbTiO_3$ piezoelectric ceramics added with 0.2, 0.25, 0.3 mol of $CaCO_3$ and 0.04 mol of $(Co_{\frac{1}{2}}W_{\frac{1}{2}})$ and 0.05 mol of $MnO_2$ and NiO have been fabricated. These ceramics can be poled sufficiently within 10 minutes at $100^{\circ}C$ under about d.c. field of 40 kv/cm. Detailed measurement was performed on dielectric constants, cutie temperatures, elastic and piezoelectric properties and coupling factors for the fabricated ceramics. The most value of the piezoelectric coupling factors was coupling factor of thickness mode kt and its value for 0.25 mol of Ca was about $45\%$. Dielectric constants of $\varepsilon_{33}^T$ and $\varepsilon_{11}^T$ for 0.25 mol of Ca were 242 and 260, and coupling factor ratio (kt/Kp) and Qm were 6 and 357 respectively.